The field of this invention relates to wood floor sanding machines.
Hardwood floors have long been a desirable trait in a home. However, sanding and refurbishing a hardwood floor is one of the more difficult do-it yourself tasks for a homeowner.
The present sanding machines on the market commonly have a single belt drive all three sanding discs which creates a side torque that drives the machine to one side as it sands the floor. The operator then needs to always counter the torque which promotes an uneven surface finishing and fatigue on the operator for larger sanding jobs.
Many machines also have higher operating speeds which allow little error in operating the machines. The high operating speeds can quickly cause gouging and knicks in the wood floor without having time to control or eliminate these gouges. Furthermore, the high operating speeds produce significant amount of noise.
Attempts have been made to increase the sanding force of the discs by increasing the weight of the sander. These weights are obtrusive horseshoe shaped steel members that are mounted on top of the sander housing. The external weights require an extra fastening device and if not tightly mounting the weights, extra chatter and vibration may occur.
These sanding machines also have a housing edge which is widely spaced from the operating sanding discs. This prevents the machine to sand close to walls. Furthermore the housing may have a high periphery which prevents it from intruding under the toe recess under many kitchen cabinets. As a result, even after adding a shoe molding to the edge of the floor, an unsanded edge may be showing. Therefore, additional smaller edge sanders need to be extensively used to approach the edge of the floor which further make the sanding process difficult.
Furthermore, the sanding creates great amount of sawdust which needs to be controlled. The sawdust if not controlled can fill the room creating a mess and interfering with the visibility of the floor as it is being sanded. Secondly, uncontrolled sawdust, particularly when air born, may under certain circumstances be combustible from sparks or other ignition sources. If a vacuum is difficult to use on a floor sander, complacency is promoted in allowing loose sawdust to accumulate.
Furthermore, for do-it yourself applications, an operator often leases or rents a machine which therefore requires the operator to carry the machine from the rental outlet. If the machine is not easily disassembled to easily carried components, the weight of the machine may cause difficulty for the operator to transport the sander between the rental place and his home.
What is needed is a floor sander that can approach an edge of a floor within the distance of an ordinary shoe molding while reducing noise, that increases control and ease of use, reduces saw dust, and provides other conveniences for making a do it yourself operation feasible.
In accordance with one aspect of the invention, a power sander for a wood floor includes a housing, and a motor mounted to the housing and having a centrally positioned downwardly extending drive shaft. An inner bowl member is positioned within the housing and is rotatably mounted on the drive shaft to allow rotation of the inner bowl with respect to both the housing and drive shaft. A plurality of pulleys are circumferentially spaced about the drive shaft and are rotatably connected to the inner bowl member. The axis of rotation of each pulley is parallel to the axis of rotation of the drive shaft. Each pulley constructed to have sander discs mounted thereon. A plurality of belts, with each belt preferably having a cogged inside and mounted about one pulley and engageably driven by the drive shaft. The drive shaft and said pulleys having respective cogged peripheries for creating a positive engagement with said inner side of the respective belts. A plurality of pulley tensioners engage the outer side of a respective belt with the outer side preferably being flat and frictionally engaged by the pulley tensioners in the form of bearings.
The belts are vertically spaced with respect to the drive shaft at a vertical position adjacent from one another. Each respective pulley is respectively vertically positioned to engage its respective belt horizontally from the engaging vertical position on the drive shaft. Each tensioner also is vertically positioned to a proper height to operably engage its respective belt.
The housing is preferably bell shaped with a downwardly extending side wall and connectable to a vacuum motor for suction of saw dust up through the bell shaped housing. The housing has an aperture for connection to a vacuum hose for allowing vacuuming of sawdust up through the housing and through the aperture. A weighted metal plate is attached to an inner bowl member, said weighted metal plate having apertures for allowing said pulley to extend therethrough. The plate has an outer periphery spaced from said side wall of said housing to define a path for the vacuuming of said saw dust.
It is desirable that a weighted plate is mounted to the inner bowl and has notches at its outer periphery to create widened gaps with the housing to increase air flow therebetween. It is also preferred that the housing has its side walls spaced within xe2x85x9c inches from a sanding disc edge. The housing has handles mounted thereon near a front and rear portion thereof and extending upwardly therefrom. The housing also has a plurality of quick connect pins that removably connect the housing to the operating handle. In accordance with another embodiment of the invention, the center drive shaft has a gear section, these gears are circumferentially spaced about said drive shaft and are rotatably mounted on the inner bowl member in a coplanar fashion and operably engage said center gear section of the drive shaft. The gears having respective pulley sections affixed thereto with the pulley sections being coplanar with each other. The plurality of pulleys are coplanar with each other and with the pulley sections. The belts are also coplanar and engage a pulley section of the respective gear and the pulleys.
In accordance with another aspect of the invention, a vacuum cleaner is mounted to the operable handle. A vacuum hose operably extends from the vacuum cleaner and is resiliently flexible and stretchable from a rest length to an increased length. The distal end of the hose having a shaped nozzle that can receive a hose coupling on the housing allowing the hose to be directly connected to the hose coupling without removal of said shaped nozzle for vacuuming sawdust out of the housing, and with said hose being detachable from said hose coupling to allow said shaped nozzle to be operably used. The vacuum is grounded to ht power sanding machine and preferably has a metal canister.